Grinding apparatus



. F. M. FURBER.

GRIND ING APPARATUS.

APPLICATION FILED JULY 30.1917.

Patented Nov. 29, 1921.

SHEETS-SHEEI Fig.1.

F. M. FURBER.

GRINDING APPARATUS.

NTU/Q Patented Nov. 29, 1921.

5 $HEETSSHEEI 2.

, yJ/W m N w Y m M m m M 5 9 2 Y Quv 3 m 1 F. M. FURBER. GRINDING APPARA TUS. APPLICATION FILED JULY 30. 19]]- 1,398,295; Patented Nov. 29, 1921.

5 SHEETS-SHEEI 3.

F. M. FURBER. GRINDING APPARATUS. APPLICATION FILED JULY 30. I917.

F. FURBER. GRINDING APPARATUS.

' 7 APPLICATION FILED JULY 30, 19]]: 1,398,295. I Patented Nov. 29, 1921.

5 SHEETS-SHEEI 5.

FHEDEBIGK 1R, 01* REVERE, MASSAGHUSETTEE, ASSIGNOR, BY IVIESNE ASSIGN- E'ZENTS, ".516 1'. n1) SHOE MACHINERY CUBPORATIQH, OF PATEFJSGH, NEW JERSEY,

A GOEPURATION 01* ll'EliV JERSEY.

GRINDING APPARATUS.

Application filed July 30,

T0 aZZ whom it may concern:

Be it known that l, FREDERICK M. FUPBER, a citizen of the United States, residing at Revere, in the county of Suiibik and State of Massachusetts, have invented certain Improvements in Grinding Apparatus, of which the following des.;ription, in COI1I1C tion with the accompanying drawings, is a specification, lilre reference characters on-the drawings indicating like parts in the several figures.

This invention relates to apparatus for rinding rotary cutters and more particuarly to such as are used for trimming the edges the soles of shoes. Such a machine or apparatus is shown in U. S. Letters Patent 1,127,877, granted February 9, 1915, on application oi F. M. Furber. These cutters are often lacking in uniformity, in that the teeth are or different thicknesses or widths circumferentially or have their working faces otherwise displaced from normal because of defects in manufacture or previous grinding. W hen such cutters are grouiui, as is common, upon an apparatus in which mechanism causes an unvai-"ylng a "vance of the cutter tooth by tooth an iount equal to the correct pitch of the eth, more material will be removed from .hose teeth whose working faces are disp aced most in a toruard direction and less mater al will be removed from the other teeth This condition may arise Where some ot the teeth become warped in tempering so that their working faces are moved from a normal position. Because oi the clearance n ular 7', i lination oi the working face hetceth this di'liercnce in the reduction the faces will also change their lengths and this tends to produce a cutter which in operation will chatter and roughen the work.

The principal object of the present invention is to provide a grinding apparatus which will discriminate with respect to the displacement oi th working faces of the teeth from normal, feeding them forward to the grinding member a distance depend-- iin; on this displacement.

To this id my improved grinding apparatus includes means not only for causing a preliminary advance of the cutter through a definite angle, but also for mak- Spccification of Letters Patent.

Patented Nov. 559, i921.

1917. Serial No. 183,496.

a corrective setting, preferably by an instrumentality contacting with the working face of the tooth next to be ground. In the embodiment of the invention herein illustrated, this setting of the cutter con sists of a predetermined angular movement, plus or minus an amount depending-upon the displacement of the working face oi the tooth.

Another feature of the invention resides in means for retaining the cutter support in its adjusted position when the cutter is being ground.

Still another feature consists of novel means whereby the cutter may be initially positioned upon the support to give a feed of the cutter tooth by tooth through an uncle different by a predetermined amount from the normal pitch angle of the teeth.

The invention also provides improved means for stopping the feed of the cutter after all the teeth have been ground, and this is eiiective with respect to the initial positioning means in a definite angular relation to determine the extent of the preliminary advance or the cutter.

An additional feature of the invention concerns means for conveniently adjusting the grinding member and cutter support relatively to one another to alter. the amount of material removed from the teeth and the extent to which a wheel enters between the teeth.

Further adjusting means are preferably provided for causing the cuttensetting men1- her to properly cooperate with the teeth and to vary the clearance of tie teeth produced by the grinding operation.

in connection with the above there are other features of novelty which will hereinafter particularly be described and pointed out in the claims.

in the accompanying drawings-9 Figure 1 is a top plan view oi one form or my invention;

Fig. 2 is a front elevation thereof;

Fig. 3 is a transverse section on the line 33 of Fig. 1, looking in the direction of the arrows;

Fig. -l is a similar view on the line l-e of 1, taken in the opposite direction;

Fig. 5 is an enlarged bottom plan view of the brake mechanism for the cutter spindle, and

Fig. 6 is an enlarged sectional detail of the means for stopping the operation of the apparatus after all the teeth of the cutter have been ground.

At 10 appears the frame of a grinding apparatus made in accordance with one embodiment of the invention this being of generally U-shape having arms 11 and 12, the arm 12 extending to a greater vertical height. Supported by a shaft 23 carried by the arm 11 is a bearing member 13 in which is journaled a shaft 14', having fixed to its inner extremity a suitable grinding wheel 15 provided with a flat face 16 with which the teeth of the cutter C to be ground may contact. The outer end of the shaft 1 1 may carry another grinding wheel 17 useful, for example, for the free-hand grinding of shanletrimming cutters. The bearing mem ber 13 is divided, having separated portions 18, 18. Between these is mounted a driving member 19, in the present instance shown in the form of a pulley, to which power may be applied through a belt from any suitable source. This pulley 19 is preferably in two sections with the outer ends adjacent to the bearing portions 18. As in grinding machines the abrasive particles thrown off from the wheel are liable to cause much wear in the bearing surfaces, the pulley 19 includes means for taking up longitudinal play of the shaft 14 resulting from this wear. This may consist of a screw 2-0 threa ed horizontally through one of the sections and hearing at its inner end against the other. W hen this screw is turned inwardly it forces the pulley sections apart, so that their outer surfaces may be brought into close proximity with the ends of the bearings. Set screws 21, 21 permit the pulley sections to be flxed in their adjusted positions.

The bearing member 13 has a lower portion 22 in which is pinned or otherwise secured a carrier shaft 23 mounted to turn in a bore in the separated portions of he arm 11. This permits the bearing member 13 to be rocked as presently described, to adjust the grinding wheel 15 toward or from the cutter C. The outer end'of the shaft 23 is recessed to receive the conical end of a screw 24- having a h and wheel 25 and being threaded through a bushing 23 mounted in the outer end of the bore and held against rotation by a lock nut 27 "l /hen the screw 2t is turned in a clockwise direction it moves the shaft 23 against a spiral spring 27 seated at the end the bore and thus shifts the bearing member 13 with the shaft and consequently adgusts the grinding wheel. away from the tooth-face of the cutter to be ground. By turning the screw 24 anti-clock wise, it retreats from the shaft 23, allowing the spring to move the grinding wheel oppositely to the previous adjustment. Arranged to turn in the arm 11 below the screw 24 is a handled rod 28 held against longitudinal movement by collars 29, 29 pinned thereon. The inner extremity of this rod carries an eccentric 3O turning in a recess in the lower end of the portion 22 of the bearing member. Rotation of the eccentric by means of this rod rocks the bearing member 13 about the axis of the shaft 23 to move the grinding wheel toward or from the axis of the cutter and thus vary the depth to which the wheel will enter between the teeth.

Journaled in the upper portion of the frame arm 12 is a shaft 31 having secured at its inner extremity an arm 32 terminating in a portion 33 lying outside the edge of the grinding wheel. The portion 33 of the arm carries a support for the cutter C to be ground comprising a post 34 in which a spindle 35 is mounted to turn As shown by comparing Figs. 1 and 3, the shaft 31 is not in alinement with the cutter shaft 141. Consequently when the shaft 31 is rotated the cutter support and the cutter C will be revolved bodily about the grinding wheel in a path that traverses the wheel during a portion of the revolution of the cutter, as more fully explained in the Patent 1,127,877 hereinbefore referred to. The spindle 35 is movable longitudinally through a sleeve 80, supported for rotation in the post 3 1 by an annular flange 81 resting upon the top of said post. The upper extremity of the sleeve 80 is made conical to enter a correspondingly tapered recess 83 in the lower end of a sleeve 84, (Fig. 41-) carried upon the spindle 35 between a head 85 pinned to the end of the upper spindle and an integral flange 86 upon the spindle situated at the bottom of the recess. Theroutside of the sleeve 84 is of such diameter as to give a sliding fit for the central opening of the cutter, and adjacent to the flange 81 this sleeve is slotted to render it expansible. A thumb nut 36 is threaded upon the opposite end of the spindle from the head 85, and when turned right-handedly forces the head against the end of the sleeve 84: causing the tapered end of the sleeve 80 to expand the divided porton of the sleeve 84 within a cut ter which has been slipped over the lastnamed sleeve and which is seated on the flange 81. This holds the cutter firmly in place so that it rotates with the spindle and sleeves. Rotation of the nut 36 in the opposite direction frees the cutter, the flange 86 separating the tapered. portions of the.

ting against and surrounding a portion of a cylindrical boss projecting from the inner vertical face of the frame arm 12. T he pawl 37 is provided with a strap 41 surrounding an eccentric 41 which is securet to the inner face of the boss 40. To enable the timing of the pawl to be changed, the fastening of the eccentric may consist of a pin 42 adapted to pass through any one of a series of openings 43 in the eccentric into the boss 40. The throw of the eccentric and the length of the teeth of ratchet 38 are such that for each movement of the pawl the cutter spindle may be turned through an angle equal to the normal pitch of the cutter to be operated upon. This effect, however, is modified by an initial separation between the end of the pawl and the ratchet teeth, as will hereinafter appear.

Carried by the arm 32 and its post 34 is a bracket 44 (Figs. 2 and 3) situated adjacent to the edge of the grinding wheel and having pivotally mounted upon it a carrier or guide member 45 (Figs. 1 and 3) for a cut ter-setting finger 46. This carrier 45 is pivoted about a bolt 47 secured by a nut 48 below the bracket 44 and having a conical head 49. Rotatable about the bolt is an eccentric sleeve 50, the outer conical recessed portion of which is forced against the conical head of the bolt by a compression spring 51. This eccentric sleeve turns within an opening in the carrier member 45 and when rotated by means of the head varies the angle at which the point of the finger 46 advances between the teeth of the cutter. The pressure exerted by the spring 51 retains the eccentric in the position to which it is adjusted. The finger 46 is arranged to move in guides 4'5, the direction of movement being circumferentially of the cutter. Teeth 48 formed in the outer edge of the finger ceiperate with a worm 49 fixedv to a spindle 50- mounted to rotate in hearings in the carrier. The worm when turned by a finger piece 51 moves the finger in its guides about the cutter, so that upon contact therewith it may be caused to effect different angular settings and thus change the clearance which results from the grinding. A compression spring 52 located between a lug 44 of bracket 44 and the end of the carrier on the opposite side of its pivot from the finger guiding extremity holds said finger normally out of the path of the cutter teeth. When the 32 and parts carried thereby are rotated as hereinbefore described, the finger is moved into cotiperation with the cutter teeth by an anti-friction roll 53 mounted upon the carrier member 45 and contacting with cam projections 54 and 55 upon the boss 40. (Figs. 1, 2 and 4.)

Below the ratchet wheel 38, conveniently integral therewith, is a friction disk 56 having a grooved periphery with which contacts a brake member 57 (Figs. 2, 3 and 5) pivotally carried by a lever 58 fulcrumed on a boss 59 projecting from the arm 32. f t the end of the lever opposite the brake is an anti-friction roll 60 running upon the surface of the boss 40 and entering during a portion of its travel a cam depression 61 therein. The roll is held in engagement with the boss and depression by a leaf spring 62 fixed to the head of the casing 39. lVhile the cutter is being advanced from the position in which one tooth has been ground to that for grinding the next, the roll 60 engages the elevated surface of the boss 40,

causing the brake member to be held away from the friction member 56. As the cutter approaches the grinding wheel in the rotation of the arm 32, the roll rides into the depression 61, permitting the spring 62 to apply the brake to the friction member and fixing the cutter spindle in position so that the tooth may be ground by the wheel.

To determine the position of the arm 32 to permit grinding to be performed manually rather than automatically, and to allow the cutter to be positioned initially for automatic operation, the casing 39 carries a detent 63 (Fig. 3) held against the edge of the boss 40 by a compression spring 64. In the edge with which the detent contacts are two notches 65 and 66. A finger piece 67 attached to the detent and projecting through the casing allows the detent to be moved out of engagement with these notches. When the detent rests in the notch 65 the arm is at such an angle that the cutter mounted upon the support 34 is in the central grinding position. When the notch 66 is engaged by the detent the angular position of the arm is such that the roll 53 of the finger carrier 1 5 rests upon the highest point of the cam projection 55. The operation of the apparatus in these respective positions will later appear more clearly.

The shaft 31 may be rotated to turn the 110 arm 32 and. thus actuate the pawl 37 by'its eccentric, move the finger carrier over the projections 54 and 55, shift the brake member 57 and bring the cutter teeth into contact with the grinding surface by a driving 115 member which may consist of a crank 67, (Figs. 1, 2 and 6) fast upon the outer end of shaft 31. To prevent the operator from turning the crank more times than is necessary to sharpen all the teeth of the cutter 1 and thus bring teeth already ground into coiperation with the grinding wheel, means is provided for automatically locking the crank at the completion of the grinding operation. This may include a controlling 125 wheel 68 mounted to turn upon a stud 69 fixed to the crank in proximity to the frame arm 12. Between the crank and the controlling wheel is a spring 70 which presses the wheel against a washer 70' at the outer l end of the stud so that though the wheel may turn upon said stud it is frictionally retained in the positionto which it is moved. The number of teeth of the controlling wheel is equal to that of the cutter to be ground, and as the crank is turned the teeth are successively brought into contact with a projection 71 upon the frame, which causes the wheel to be advanced by an amount equal to the pitch of the teeth. In the face of the wheel 68 adjacent to the crank is a notch 72 to receive an enlargement 73 upon a latch member 73 pivoted upon the crank and pressed against the wheel by a leaf spring 74. When the wheel has been so rotated that the enlargement 7 3 may enter the notch 72, a portion of said enlargement also engages a depression 74 formed in the machine frame. It will be seen that starting with the latch resting upon the face of the controlling wheel adjacent to the notch 72, for each turn of the crank the notch will be moved away from the latch one tooth by the engagement of the teeth with the projection 71. When the wheel has made a complete turn and all the teeth of the cutter have been ground, the notch 72 again reaches the latch, allowing it to-enter the depression 74 and lock the crank.

In the use of this apparatus, the operator places the cutter to be ground upon the spindle 35, and if the teeth are of unequal length leaves the thumb nut 36 loose and turns the crank 67' until the detent 63 en gages the notch 65. At this time the arm 32 is in such an angular position that the working face 0 of the cutter which is to be ground cooperates with the surface 16 of the grinding wheel, as is illustrated in Figs. 1 and 2 of the drawings. The cutter may be now manually turned upon the spindle to grind the tooth presented to it to any desired extent and after turning the crank sufficiently for the cutter to clear the wheel, said outter may be manually turned upon the spindle to bring any other unduly long tooth into the grinding position. After the cutter has been thus manually trued as to the length of the teeth, it is prepared for automatic grind ing by rotating the crank until the detent 63 enters the notch 66, at which time the roll 53 upon the finger carrier rests upon the high portion of the, cam projection 55, swinging the carrier about its pivot until the point of the finger 16 lies in the path of the cutter teeth. To enable the finger to properly clear the ends of the teeth in its oscillation, the angular position of the eccentric 50 may be varied, andjthe location of the finger circumferentially of the cutter may be altered by rotation of the worm l9 to give the proper inclination to the working face 0. This face of the tooth then adjacent to the wheel is brought into contact with the surface 46' of the finger and the cutter fixed upon the spindle by tightening the nut 36. This initially positions the cutter teeth a predetermined distance beyond that position at which a normal tooth would be ground, say a sixteenth of an inch, which would be sufiicient to cover any irregularities in this dimension. At this time the contact end of the pawl 37 is a corresponding distance from the vertical face of the ratchet tooth with which it cooperates. By means of the eccentric 30 the bearing member'13 is rocked so as to adjust the grinding wheel to cause it to enter between the teeth to the required depth and the bearing member is adjusted by the screw 24: to cause the grinding wheel to remove the proper amount of material to sharpen the teeth. Now the crank 67 may be turned continuously to complete the grinding operation for the entire cutter. During each revolution of the arm 32, the roll 60 of the brake lever rides upon the surface oft-he boss l0 and passes beyond the cam depression 61, holding the brake temporarily away from the friction surface 56 and leaving the cutter spindle 35 free to turn. The setting linger as, as the roll 53 leaves the cam'projection 55, is withdrawn from between the teeth and the pawl 37 acts to advance the cutter in the direction of the heavy arrow in Fig. 1 through an angle equal to the normal pitch of the cutter teeth less that produced by the initial setting of the cutter. Then as the advance continues the roll 53 reaches the higher cam projection 5% and the finger again swings in so that its surface 46 engages the working face 0 of the next tooth to be ground, rotating the cutter back in a counter clockwise direction a distance equal to the initial setting of the face 0, or a sixteenth of an inch. If the tooth has its working face in a normal position this correcting movement will result in a net advance of the cutter equal to the nor mal pitch. If the tooth next to be ground has its working face displaced forwardly, the cutter will be turned back so much farther and therefore the net advance will b less. If the tooth has its working face displaced rearwardly, the correcting movement will be less and the total advance will be greater. The cutter having been thus set during that portion of the rotary travel of the arm which causes the cutter to follow a curved path eccentric to and outside the periphery or edge of the grinder, the continued travel of the arm 32 causes the roll 60 to be forced by the spring 62 into the depression 61 applying the brake 57 to hold the spindle 35 against rotation. The tooth to be ground thereupon passes across the face 16 of the wheel, and because of the corrective action of the setting finger upon this tooth there is at all times such an amount of .setting of said cutter.

material removed that the sharpened teeth are of equal length. The mechanism described, as will now be understood, provides means for effecting a preliminary setting of the cutter and means for making a corrective In other words the support which carries the cutter is rotatively movable relatively to the grinding wheel a distance 'which depends upon the displacementof the working faces of the teeth to be ground. The finger 46, by contacting with the tooth next to be ground and actuated through the instrumentality of the pawl 37, effects a feed of the cutter a distance which depends upon this displacement. Upon each turn of the crank 67 the controlling wheel 68 thereonis rotated one tooth by engagement with the projection 71; and after all the teeth have been operated upon, the apparatus is positively locked against movement by the entrance of the projection 7 3 into the notch 74 until freed by the opera tor for grinding another cutter. The position of the notch 7lis such that when the arm 32 is stopped the roll 53 of the finger carrier has reached a point somewhat be yond the cam projection 55. This so advances the ratchet wheel, that upon drawing the arm back until the roll 53 rests upon the projection 55 in setting another cutter to beground, the end of the pawl 37 will be moved far enough away from the engaged ratchet tooth to reduce the angle through which the cutter is turned by the pawl an amount equal to the corrective movement in the opposite direction. imparted by the projection 54;. 7

While I have described this grinding apparatus as receiving power through a crank, it may be driven from any suitable motor. For this purpose I have shown fast upon the shaft 31 an eccentric gear 7 5 (Fig. 1), mesh ing with a similar gear 7 6 loose upona shaft 77 journaled in the frame arm 12 parallel to the shaft 31. The gear 76 may be secured to turn with the shaft 7 7 by the clutch 7 8, which I have illustrated as of the friction-disk type and operated by a lever 79 connected to a treadle, not shown. The shaft 77 may be constantly rotated by spiral gearing 8? connecting it with a power shaft 88. The eccentric gear 75 is so fastened to the shaft 31 that it imparts most rapid movement to the arm 82 while the cutter is subject to the setting operations, and upon its reaching the grinding wheel advances it more slowly so that it is effectively ground. Many other changes in the apparatus may obviously be made and are to be considered as within the scope of the invention.

Having thus described my invention, I claim as new and desire to secure by Letters Patent of the United States l. In combination, a grinding wheeha cutter support, and means for rotating the wheel and support relatively to one another through varying distances depending upon the displacement of the working faces of the teeth to be ground.

In combination, a grinding wheel, a retatable cutter support, and means including an element contacting with the tooth next to be ground for feeding the cutter a distance depending upon the displacement from normal of the working face of said tooth.

3. A cutter grinding apparatus comprising a cutter support, means for making a preliminary setting of the cutter, and means for making a correcting setting of said outter.

4:- A cutter grinding apparatus comprising a cutter support, automatic means for making a preliminary setting of the cutter.

and automatic means for making a correcting setting of said cutter.

5. A cutter grinding apparatus comprising a cutter support, means for turning the cutter through a definite angle, and means for turning the cutter through a variable angle.

6. A. cutter grinding apparatus comprising a cutter support, means for turning the cutter through a definite angle, and means cooperating with the tooth next to be ground for turning the cutter through avariable angle.

7. A. cutter grinding apparatus comprising a cutter support, means for turning the cutter an amount bearing a predetermined relation to the normal pitch of the teeth, and means for turning the cutter an amount depending upon the displacementfrom nor mal of the working face of a tooth.

8. The combination with a grinding wheel, a cutter support and means adapted to rotate the cutter to advance it tooth by tooth to the wheel through a predetermined angle, of means whereby the cutter may be initially set on the support to cause the advancing means to'turn the cutter through an angle different from said predetermined angle.

9. The combination with a grinding wheel, a cutter support and means adapted to rotate the cutter to advance it teeth by teeth to the wheel through a predetermined angle, of means whereby the cutter may be initially set on the support to cause the advancing means to turn the cutter through an angle different from said predetermined angle, and means for turning the cutter in the opposite direction an amount depending on the displacement from normal of the working face of the tooth next to be ground.

10. The combination with a grinding wheel, a cutter support and means for rotating the cutter to advance it tooth by tooth to the wheel through a predetermined angle, of

ter tooth whereby the cutter may be initially set on the support to cause the advancing means to turn the cutter through an angle less by a predetermined amount than the pitch angle of the teeth, and means for turning the cutter in the opposite direction said predetermined amount plus or minus an amount depending upon the displacement of the working face of the tooth next to be ground.

11. The combination with a grinding wheel, a cutter support and means for rotating the cutter to advance it tooth by tooth to the wheel through a predetermined angle, of means whereby the cutter may be initially set on the support to cause the advancing means to turn the cutter through an angle different from said predetermined angle, and automatic means for stopping the advance of the cutter after all the teeth have been ground, the stopping means and setting means having a predetermined angular relation to one another.

12. The combination with a grinding wheel, a cutter support and means for rotatingthe cutter to advance it tooth by tooth to the wheel through a predetermined angle, of means including a finger whereby the cutter may be initially set on the support to cause the advancing means to turn the cutter through an angle different from said predetermined angle, and automatic means for stopping the advance of the cutter after all the teeth have been ground, said stopping means becominge'dective after the operating point of the setting means has been passed.

13. The combination with a grinding wheel, of a rotatable cutter support revoluble about the grinding wheel, i'eed mechanism tor the cutter including a ratchet wheel rotatable with the support and a pawl engaging the ratchet wheel, means effective at a particular point in the revolution of the support whereby the cutter may be initially positioned upon said support, and means for stopping the feed of the cutter, said stepping means being efiective after the positioning point has been passed.

14-. In a grinding apparatus, a revoluble work support, a plurality of movable means for imparting feeding movement to the work, and relatively fixed members for actuating said means.

15. In a grinding apparatus, a revoluble work support, a plurality of movable means for imparting feeding movement to the work, relatively fixed members for actuating said means, and means whereby each of said feeding movements may be. varled.

16. In a machine of the class described, a

grinding member, a work support mounted to revolve around the grlndlng member,

means revolving with the support for ro--- actuating means may be fixed in different positions.

1'7. In a machine of the class described, a grinding member, a work support mounted to revolve around the grinding member, an oscillatory cutter-setting member mounted upon the support for cooperation with the cutter, and a fixed contact member for oscillating the said member.

18. A. revoluble cutter support, an oscillatory cutter-setting member mounted upon the support for cooperation with the cutter, a fixed contact member for oscillating the said member, and a second fixed contact member serving to determine the position of the setting member in the initial setting of the cutter.

19. A. cutter support, a guide member pivoted thereon, a cutter-setting member movable in the guide member, and means for oscillating the guide member about its pivot.

' 20. A cutter support, a guide member pivoted thereon, a cutteretting member movable in the guide member, rotatable means for adjusting the setting member in the guide member, and means for oscillating the guide member about its pivot.

21. A cutter support, an eccentric carried thereby, a guide member pivoted upon the eccentric, a cutter-setting member movable in the guide member, and means for oscillating the guide member about the eccentric.

22. In a cutter rinder the combination with a frame, of an arm rotatable th reon,

523. In cutter grinder, the combination with a frame, of an arm rotatable thereon, a cutter support carried by the arm, and a setting member movably mounted upon the support for contact with the cutter, there being cutter-adjusting and cutter-actuating projections fixed to the frame for co6peration with the setting member.

24. In a cutter grinder, the combination with a frame, of an arm rotatable thereon, a cutter support carried by the arm, a setting member movably mounted upon the support for contact with the cutter, there being a cutter-adjusting projection fixed to the frame for cooperation with the setting member, and means tor determining the position of the arm at which the setting mcmher and projection are in cooperation.

25. In a cutter grinder, the combination with a frame provided with a depression, of an arm rotatable on the frame, a cutter support carried by the arm, a setting member movably mounted upon the support for contact with the cutter, there be ng a cutter adjusting projectionfixed to the frame for cooperation with the setting member, and a 7 member.

detent mounted upon the arm and engaging the frame depression when thesetting memher and projection are in cooperation.

26. it. cutter grinder comprising a grinding wheel, a rotatable cutter support, means for revolving the support around the wheel to cause the cutter to engage the grinding wheel, retaining means for the support, and means for applying the retaining means when the cutter is in contact with the grinding wheel.

27. In a cutter grinder, the combination with a frame, of a grinding wheel mounted to turn therein, an arm rotatable upon the frame, a cutter support rotatable with said arm, a retaining member carried by the arm and cooperating with the support, and means fixed to the frame for actuating the retaining member when the arm rotates.

28. In a cutter grinder, the combination with frame, of a grinding wheel mounted to turn therein, an arm rotatable upon the frame, a cutter support rotatable in the frame and being provided with a friction surface, a lever fulcrumed upon the arm and being arranged to engage the friction surface, and meansfixed to the frame for actuating the lever.

29. In a grinding apparatus, a cutter support, a grinding wheel, a shaft therefor,a support for the shaft, means for swinging the shaft support on an axis parallel to the grinding wheel shaf, and means for moving the shaft support longitudinally of said axis to position the grinding wheel and cutter with respect to one another.

80. In a grinding apparatus, a cutter supporting member, a grinding wheel and its shaft, a bearing member for the shaft, and means for sliding and rocking saidbearing member whereby the axis of the cutter and grinding surface are given a relative movement transversely and toward and from one another.

31. a grinding apparatus, a cutter support, a grinding wheel shaft,a bearing member for the shaft, a shaft to which the bearing member is fixed, means for turning the last-named shaft, and means for moving said shaft longitudinally.

32. In a grinding machine, a frame, a cutter support and a grinding wheel shaft mounted thereon, a carrier shaft journaled in the frame and being movable longitudinally therein, a bearing member for the grinding wheel shaft fixed to the carrier shaft, a spring for normally holding the.

arrier shaft in one direction, a screw for moving the carrier shaft longitudinally a ainst the spring, and an eccentric for turning the carrier shaft and bearing In a cutter grinder, the combination with grinding means and a cutter support, of mechanism including a driving member min a cutter grinder, the combination 0 With grinding means and cutter support,

of mechanism including a crank for automatically advancing tooth by tooth the cutter to be ground, and means carried by the crank for stopping the advance of the cuttor after all the teeth havebeen operated upon.

35. Ina cutter grinder, the combination with grinding means and a cutter support, of mechanism including a driving member for automatically advancing tooth by tooth the cutter to be ground, a member movable a step upon the advance of each tooth, and a latch carried by the driving member controlled by the step-by-step member.

36. In a cutter grinder, the combination with grinding means and a cutter support, of mechanism including a driving member for automaticallly advancing tooth by tooth the cutter to be ground, a toothed member, relatively fixed means cooperating with the toothed member to advance it one tooth for each rotation of the driving member, and a latch controlled by the toothed member for locking the driving member.

37. In a cutter grinder, the combination with grindingmeans and a cutter support, of mechanism including a driving member for automatically advancing tooth by tooth the cutter to beground, a wheel rotatable upon the driving member and being provided with a recess, means for turning the wheel one tooth for each turn of the drivingmember, and a latch pivoted upon the driving member and made effective by entering therecess in the wheel.

38. The combination with a grinding wheel, of a cutter support, means for revolving the support to bring the cutter into contact with the wheel during a portion of each revolution, and means whereby the rate of revolution is decreased during the time of contact between the cutter and wheel.

89. Tie combination with a grinding wheel, of a cutter support, a shaft for re including a member contacting with a cutter ling members the resultant action of which tooth for reversing the rotation of the cutfeeds each cutter tooth a distance varying 10 ter a distance depending on a characteristic with the displacement of the working face of said tooth. of the tooth from normal.

5 4-2. In a cutter grinding apparatus, a In testimony whereof I have signed my grinding wheel, a cutter support, and 'mechname to this specification. anism for feeding a cutter forward tooth i by tooth, said mechanism comprising :Eeed- FREDERICK M. FURBER.

It is hereby certified that in Letters Patent No. 1,398,295, granted November 29,

1921, upon the application of Frederick M. Furber, of Revere, Massachusetts, for

an improvement in Grinding Apparatus, an error appears in the printed specification requiring correction as follows: Page 2, line 104, for the Words end of the upper read upper and of the; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 31st day of January, A. D., 1922.

[SEAL] WM. A. KINNAN,

Acting Commissioner of Patents. 

